Some example embodiments relate to detecting a Bluetooth page signal using a wideband receiver.
Bluetooth devices use frequency hopped transmissions to provide resilience to fading and manage radio-frequency (RF) interference. Reception of frequency-hopped transmissions, such as Bluetooth transmissions, is generally accomplished using a narrowband receiver. Such a narrowband receiver includes a frequency-hopping local oscillator that hops independently of a transmitter of the frequency-hopped transmissions. Synchronization is established when a frequency hop of the transmitter coincides with a frequency hop of the local oscillator.
During a Bluetooth page scan, the scanning Bluetooth device hops slowly by staying on one hop frequency for an entire scan window, while the paging Bluetooth device hops quickly by alternating between two trains of 16 channels every 10 ms. When the paging Bluetooth device transmits on the hop frequency the scanning Bluetooth device is listening on, the page packet is received and decoded. If the decoded packet is a paging packet addressed to the scanning Bluetooth device, a connection between the two devices is established.
Page scanning is an ongoing, background operation that is periodically performed by a page scanning device. The power consumed during page scanning increases according to the current drawn by the receiver of the page scanning device while enabled and the length of time that the receiver is enabled.